This disclosure relates to an eye test assembly, and more particularly to an eye test assembly that displays an eye chart on a computer monitor and the eye test is run by software or a conventional vision test shown a projector display. Further, the present disclosure relates to a glare assembly for use with such a display or monitor that is useful in diagnosing cataracts or other ocular problems or issues associated with a patient. Under normal testing conditions, a patient may demonstrate acceptable scores, for example even exhibiting 20/20 vision in an examination room under normal exam room conditions. Unfortunately, in the light of day, and in real world conditions, such as driving at night with on-coming headlights directed at the driver, or in bright sunlight, the patient's vision may be quite different due to bright light passing through the lens of the eye.
There are a couple of different products presently on the market that test for the impact of glare, for example, a Brightness Acuity Tester (BAT), as shown and described in U.S. Pat. No. 4,784,483. The disclosure of that patent is hereby incorporated by reference. An upright handle positions an open sided housing having an aperture or opening through the housing adjacent a patient's eye. A source of illumination is disposed in the housing and is varied between high, medium, and low settings. In this manner, a patient's vision is measured in a standard manner, and with one eye occluded, the brightness acuity tester is held adjacent the patient's eye under examination, the source of illumination turned on, and visual acuity of that eye is then measured with the patient looking through the glare light. In other words, glare light is purposefully introduced into the visual path of the patient. The comparison between these acuity testing procedures under non-glare and glare conditions will then determine whether the patient has any pronounced or recognizable change in acuity vision. This may be an indication of whether cataracts or other ocular problems exist.
Another type of commercially available device is one sold by Vector Vision. An illuminated eye chart box, or light box, for example the type as shown and described in U.S. Pat. No. 5,078,486, is modified to include first and second halogen lights secured on either side of the light box. The halogen lights are described as simulating an on-coming car with headlamps illuminated at a preselected distance. The halogen lights are either turned on or off. A particular line or row of characters on the light box is illuminated. An internal light source generates the desired light intensity on a particular row of the eye chart, and employs a sensor or photocell to monitor the light intensity in the ambient environment adjacent the eye chart. In this manner, the amount of light generated by the light source can be altered.
Although commercially successful, improvements are desired, particularly when used with a vision testing arrangement.